The present invention relates to abrasive articles (e.g., abrasive wheels) comprised of abrasive agglomerate particles dispersed within cellular polymeric material, and methods of making and using the abrasive articles.
Abrasive articles comprising abrasive particles coated on and/or dispersed within an organic cellular or foam substrate (e.g., polyurethane) are well known. Examples of such articles include pads, sheets, discs, and wheels (see, e.g., U.S. Pat. Nos. 2,780,533 (Hurst), 2,885,276 (Upton, Jr.), 2,972,527 (Upton, Jr.), and 3,252,775 (Tocci-Guilbert)). These articles have been employed to abrade a variety of workpieces, including metal and wood. They have also been adapted for abrading operations ranging from coarse dimensioning operations such as xe2x80x9csnaggingxe2x80x9d to fine finishing operations such as polishing and buffing.
Abrasive articles comprising abrasive particles dispersed within and/or adhered to a polyurethane cellular or foam matrix have been used, for example, to impart a final refined surface finish on metal (e.g., steel, stainless steel, aluminum, titanium or titanium alloys) substrates designed for use in any of many applications. In finishing such substrates, what is desired is the ability to repeatedly, from part to part, impart a finish to the metal surface, conform to the design features of the metal surface, and not leave residual abrasive article material (xe2x80x9csmearingxe2x80x9d) on the finished metal surface. Current cellular or foam abrasives do not concurrently provide the desired level of each of these features.
The present invention provides abrasive articles (e.g., an abrasive wheel). Abrasive articles according to the present invention include abrasive articles comprised of abrasive agglomerate particles dispersed within cellular (i.e., having voids dispersed throughout) polymeric material, the abrasive agglomerate particles comprised of abrasive grains and a polymeric matrix formed from a radiation curable polymerizable binder precursor, wherein the abrasive agglomerate particles have a substantially constant cross-sectional area and a crush strength greater than 1 lb. (0.454 kg). Preferably, the polymeric material comprises polyurethane.
Preferably, abrasive articles according to the present invention have at least 25 percent void volume, more preferably, at least 45 percent void volume, and even more preferably have in the range from 50 to 85 percent by void volume.
In another aspect, abrasive articles according to the present invention are preferably further comprised of lubricant (e.g., metallic salts of fatty acids, fatty acid esters, solid lubricants, and mineral oils and waxes, and poly(dimethylsiloxane) gums).
In another aspect, the present invention provides a method of abrading a surface, the method comprising:
providing an abrasive article according to the present invention, the abrasive article having an outer surface;
frictionally contacting at least a portion of the outer surface of the abrasive article with a surface of a workpiece; and
moving at least of one the outer surface of the abrasive article or the surface of the workpiece relative to the other to abrade at least a portion of the workpiece surface. The method may include the use of a buffing compound, wherein the buffing compound is on at least a portion of the outer surface of the abrasive article.
Embodiments of abrasive articles according to the present invention are preferably flexible, conformable, and lightweight. Preferred abrasive wheels according to the present invention can be run smoothly and exhibit less xe2x80x9cchatterxe2x80x9d than conventional abrasive wheels. Further, preferred abrasive wheels according to the present invention can utilize less abrasive grain material than conventional abrasive wheels. Preferred abrasive articles according to the present invention also tend not to xe2x80x9csmearxe2x80x9d during use. Smearing, which is typically undesirable, can occur when a workpiece in contact with an abrasive article becomes sufficiently hot such that portions of the abrasive article soften and transfer to the workpiece.